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Let a,b,c be positive real numbers in H...

Let a,b,c be positive real numbers in H.P.
Statement -1: `(a+b)/(2a-b)+(c+b)/(2c-b)ge4`
Statement-2: `(a)/(b)+(b)/(c)+(c)/(a)ge3`

A

Statement -1 is true, Statement -2 is True, Statement -2 is a correct explanation for Statement for Statement -1.

B

Statement -1 is true, Statement -2 is True, Statement -2 is not a correct explanation for Statement for Statement -1.

C

Statement -1 is true, Statement -2 is False.

D

Statement -1 is False, Statement -2 is True.

Text Solution

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To solve the problem step by step, we will analyze both statements given that \( a, b, c \) are positive real numbers in Harmonic Progression (H.P.). ### Step 1: Understanding Harmonic Progression If \( a, b, c \) are in H.P., then the reciprocals \( \frac{1}{a}, \frac{1}{b}, \frac{1}{c} \) are in Arithmetic Progression (A.P.). This means: \[ \frac{1}{b} = \frac{1}{2} \left( \frac{1}{a} + \frac{1}{c} \right) \] From this, we can express \( b \) in terms of \( a \) and \( c \): \[ b = \frac{2ac}{a+c} \] ### Step 2: Analyzing Statement 1 We need to prove: \[ \frac{a+b}{2a-b} + \frac{c+b}{2c-b} \geq 4 \] Substituting \( b = \frac{2ac}{a+c} \) into the expression: 1. **Calculate \( a + b \)**: \[ a + b = a + \frac{2ac}{a+c} = \frac{a(a+c) + 2ac}{a+c} = \frac{a^2 + ac + 2ac}{a+c} = \frac{a^2 + 3ac}{a+c} \] 2. **Calculate \( 2a - b \)**: \[ 2a - b = 2a - \frac{2ac}{a+c} = \frac{2a(a+c) - 2ac}{a+c} = \frac{2a^2 + 2ac - 2ac}{a+c} = \frac{2a^2}{a+c} \] 3. **Calculate \( c + b \)**: \[ c + b = c + \frac{2ac}{a+c} = \frac{c(a+c) + 2ac}{a+c} = \frac{ac + c^2 + 2ac}{a+c} = \frac{c^2 + 3ac}{a+c} \] 4. **Calculate \( 2c - b \)**: \[ 2c - b = 2c - \frac{2ac}{a+c} = \frac{2c(a+c) - 2ac}{a+c} = \frac{2ac + 2c^2 - 2ac}{a+c} = \frac{2c^2}{a+c} \] 5. **Substituting back into the inequality**: \[ \frac{a+b}{2a-b} + \frac{c+b}{2c-b} = \frac{\frac{a^2 + 3ac}{a+c}}{\frac{2a^2}{a+c}} + \frac{\frac{c^2 + 3ac}{a+c}}{\frac{2c^2}{a+c}} = \frac{a^2 + 3ac}{2a^2} + \frac{c^2 + 3ac}{2c^2} \] 6. **Simplifying the expression**: \[ = \frac{1}{2} \left( \frac{a^2 + 3ac}{a^2} + \frac{c^2 + 3ac}{c^2} \right) = \frac{1}{2} \left( 1 + \frac{3c}{a} + 1 + \frac{3a}{c} \right) = 1 + \frac{3}{2} \left( \frac{c}{a} + \frac{a}{c} \right) \] 7. **Applying AM-GM inequality**: \[ \frac{c}{a} + \frac{a}{c} \geq 2 \implies 1 + \frac{3}{2} \cdot 2 \geq 4 \] Thus, Statement 1 is proven: \[ \frac{a+b}{2a-b} + \frac{c+b}{2c-b} \geq 4 \] ### Step 3: Analyzing Statement 2 We need to prove: \[ \frac{a}{b} + \frac{b}{c} + \frac{c}{a} \geq 3 \] Using the AM-GM inequality: \[ \frac{a}{b} + \frac{b}{c} + \frac{c}{a} \geq 3 \sqrt[3]{\frac{a}{b} \cdot \frac{b}{c} \cdot \frac{c}{a}} = 3 \] Thus, Statement 2 is also proven. ### Conclusion Both statements are true, but Statement 2 does not explain Statement 1.

To solve the problem step by step, we will analyze both statements given that \( a, b, c \) are positive real numbers in Harmonic Progression (H.P.). ### Step 1: Understanding Harmonic Progression If \( a, b, c \) are in H.P., then the reciprocals \( \frac{1}{a}, \frac{1}{b}, \frac{1}{c} \) are in Arithmetic Progression (A.P.). This means: \[ \frac{1}{b} = \frac{1}{2} \left( \frac{1}{a} + \frac{1}{c} \right) \] From this, we can express \( b \) in terms of \( a \) and \( c \): ...
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